Floor mats have been used in the past in a water-filled environment such as in or adjacent a bathtub or shower stall. That is, the floor mats are placed in an environment wherein they are partially or wholly immersed in water and the surrounding atmosphere has a correspondingly high moisture content. A mat is placed on the bottom of the bathtub, the floor adjacent the bathtub or another surface in the water-filled environment and presents an upper surface which frictionally engages feet or other human body parts. The floor mat enables a user to enter or leave the bathtub or shower stall and to walk about the water-filled environment safely without accidental slipping caused by the water.
One conventional floor mat design is a flexible elastomeric or rubber sheet having an embossed upper surface and a plurality of suction cups on a lower surface, such as disclosed in U.S. Pat. No. 3,034,140 to Reynolds. When the floor mat in Reynolds is pressed on a surface, the suction cups are compressed and secure the floor mat to the surface. The floor mat may be removed by forcibly disengaging the suction cups from the surface. However, this design is undesirable in several respects. Such a floor mat is relatively expensive and is intended for extended and repeated use. Sanitation is a primary concern in water-filled environments where disease causing bacteria, fungus, mildew and other organisms are commonly found. Over time the floor mat will become unsightly and a sanitation hazard due to the accumulation of these organisms on its surface. Diseases may be transferred by contact between multiple users of the floor mat, particularly in applications such as hotels and motels. Cleaning the mat is tedious, time consuming, labor intensive and therefore expensive, and is not always completely effective in sanitizing the floor mat. Finally, the suction cups are subject to deterioration over time and slippage of the floor mat may occur with respect to surface on which it is mounted.
One alternate design is a floor mat consisting of one or more plastic strips permanently adhered by an adhesive to a surface in a water-filled environment. The strips have a roughened upper surface. If left on the surface permanently, the adhesive on the strips may lose its tack over time due to the absorption of water and moisture from the environment. For the purposes of this application, "tack" is the property of an adhesive that enables it to form a bond of measureable strength immediately after being brought in contact with a surface under low pressure. If the deterioration of the adhesive continues, the strips may slip with respect to the surface, creating an obvious safety hazard. Moreover, this type of floor mat is even more difficult to maintain in a sanitary condition than the suction cup type floor mat which may at least be removed and cleaned periodically. Dirt and other contaminates also have an undesireable tendency to accumulate on and around the strips. Although relatively inexpensive compared to the suction cup type mat, adhesively applied strips are not intended for frequent replacement. Even if the strips are somehow removed, stringing or webbing is likely to occur in which at least a portion of the adhesive film is separated from the undersides of the strips and is deposited on the surface in the water-filled environment.
Disposable floor mats have been developed which attempt to avoid the sanitation and other problems associated with the floor mats previously discussed. U.S. Pat. No. 4,328,275 to Vargo discloses, an example of this type of disposable floor mat. In Vargo, the floor mat includes a liquid absorbing layer having a series of raised portions. The raised portions are treated with a liquid repellent to direct water and other fluids into the absorbent layer to avoid contact with a human foot. The bottom layer of the floor mat is impervious to liquids and is in contact with a surface to secure the floor mat thereto.
However, disposable floor mats such as disclosed in Vargo do not adequately relieve all of the problems associated with conventional floor mats. Specifically, Vargo relies solely on surface friction between the bottom surface of the floor mat and the surface on which the floor mat is placed to prevent the floor mat from slipping. This is frequently inadequate, particularly if the floor mat is applied over a preexisting layer of water on the surface which drastically reduces the coefficient of friction of the surface. Walking on the floor mat places a large and sudden lateral force on the mat, with obvious consequences if the floor mat is not secured properly. Moreover, by absorbing water and other fluids the weight of the floor mat is increased, making disposal of the mat more difficult.